Mesa/Boogie F-30, F-50, F-100 owner manual Combination Series & Parallel

SPEAKER IMPEDANCE MATCHING & HOOK-UP GUIDE: (Continued)

PARALLEL:

When wiring in parallel, the resistance of the speakers decreases. Two 8 ohm speakers wired in ( hooked-up ) Parallel results in a 4 ohm load. It’s easy to calculate the effect of a resistive load when all the speakers are all the same resistance. It is really not suggested to wire different resistive load values in Parallel ( 8 and 4, 16 and 8 etc. ) The formula for figuring the total impedance in Parallel is the multiplication of the two loads divided by the sum of the two loads - i.e. putting two 8 ohm speakers in Parallel results in a 4 ohm load. Connect the Positive side of Speaker A to the Positive side of Speaker B - Connect the Negative side of Speaker A to the Negative side of Speaker B.

Speaker A

8 Ohms

			S
	K		H
C		Made by
A				D
		Electro-Voice			O
L					W
B

Total Load = 4 Ohms

Speaker B

8 Ohms

			S
	K		H
C		Made by
A				D
		Electro-Voice			O
L					W
B

NEGATIVE

POSITIVE

COMBINATION SERIES & PARALLEL:

This is really just two sets of Parallel wired speakers connected in series. This is how you maintain a consistent load with multiple speakers. The importance of this is more evident when you have more than one cabinet to connect to your amplifier.

								This is when you need to figure out the loads and how to
			All 4 Spkrs.are 8 Ohms					wire them up without applying too low of a resistance on the
								amplifier.
SPEAKER A				SPEAKER B
		S				SH		Simply connect the Positive side of Speaker A to the Posi-
	K						A
		H				Made by D		tive side of Speaker C.
	Made by		D	C Electro-Voice
C Electro-Voice				A			O
A			O	L			W
L			W	B
B								Connect the Negative side of Speaker A to the Positive side
								of Speaker B, then on to the Positive side of Speaker D and
								finally on to the Negative side of Speaker C.
SPEAKER C				SPEAKER D				And lastly, connect the Negative side of Speaker B to the
								Negative side of Speaker D.
		S			K		SH	4 Eight ( 8 ) Ohm speakers wired in Series Parallel = a Total
	K	H
			A	C		Made by		Load of 8 Ohms.
	Made by		D
	Electro-Voice			A	Electro-Voice
			O	L
			W
				B

POSITIVE NEGATIVE

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